Fan



A. w. CARLSON,

FAN.

APPLICATION FILED JULY 11,1919.

1,370,284. Patented-Mar. 1,1921.

laping inner portions. 2o'

` AXEL W. CARLSON, OI' WORCESTER,

` UNITE-D STATES PATENT oFFicE.

MASSACHUSETTS, ASSIGNOR TO CARLING TUR- Bm BLOWER CO., 0F WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSA- Application led July 11, -1919. Serial No. 310,004.

Patented Mar. 1,1921.

CHUSETTS.

FAN. I

1,370,284. Specification of Letters Patent.

To allwhom it may concern Be it known that I, Am. W.- GAnLsoN, a citizen of the United States, residing at Worcester in the county of Worcester and State of Massachusetts, have invented a new kand useful Fan, of which the following is a specification. 1

invention relates to a fan'capable of general use but particularly designed for a turbine blower.

It is the object of my invention to providev a fan so `constructed that increased efficiency ma be attained.

ith this object in view, an important feature of my invention relates to the pro-A vision of fan blades angularly disposed relative to the axis of the fan and having overherfeatures-of my invention relate to the curvature and outline of the separate blades and also tothe provision of blades of unusual width in relation to their length.

My invention further relates to. the design and arrangement of parts hereinafter described and more particularly pointed out l in the ap nded claims.

A erred form of my invention is shown in the drawing in 'whichf Figurel is a front view of my improved an; v

Fig. 2 is a side elevation thereof, and Figs. 3, 4 and 5 are Sectional views taken along the lines 3 3, 4-4 and 5-5 in Fig. l. My improved Afan comprises a hub or bearing portion 10 to which a plurality of fan blades 11 are secured, the hub and blades vbeing preferably castl as' an integral struc- The blades are disposed atfan angle to the.

axis of the .fan and are. of such width that the portions adjacent the hub overla.p each' other, as is clearly shown in Fig. 1. y

The4 blades are ofuuusual width, bein substantially equal in le h-and breadt and' substantially Aofthe circumference o the fan at their outer edges.

The radial edges of the' blades are prf erably disposed in Ysubstantially lparallel structed to'embody'the features above de`- scribed possesses very` much .greater ediciency than the ordinary fans heretofore used, theincrease in eiciency in some cases amounting to from 75 to 100 per cent.

Having thus described my invention, it will be evident that changes and modifications can be made therein by those skilled in the art within the spirit and scope of my invention as set forth in the claims, and I do not wish to be otherwise limited to the de? tails herein disclosed.l

1. Afan comprising a-hubA and a'plurality of blades mounted thereon and having their base portions disposed at an oblique angle to the axis, the radial section of each blade vincreasing in curvature toward the rear edge, the front and rear radial edges of the blades lying substantially in' parallel planes perpendicular to the axis and being reversely curved outwardly in said plane, and the radial edges of each blade being substantially perpendicular to the circumferential edge thereof.

2. Afan comprisinga hub and a yplurality of blades mounted thereon and having their base portions disposed at an oblique angle to the axis, the front and rear radial edges of the blades lying in substantially parallelv planes perpendicular to the axisvbut being reversely curved outwardly in said planes. In testimony whereof have hereunto aixed my signature. l

- AXEL W. CARLSON. 

